Alloy



United States Patent ALLOY Herman L. Mann, New York, N. Y.

No Drawing. Application August 26, 1953, Serial No. 376,759

4 Claims. (Cl. 75-171 This invention relates to metal alloys and moreparticularly to metal alloys having an advantageously low' fusing pointand better flow properties.

It is an object of this invention to; provide an alloy endowed withspecial characteristics.

It is another object of this invention to provide an alloy having goodflow properties and a low fusing point.

It is still another object of this invention to provide an alloy whichis economical and has a low atomic weight so as to provide substantialvolume at a lesser density.

Still another object of this invention is the provision of an alloywhich is resistant to acids.

A still further object of this invention is to provide an alloy forcasting which produces a smoother surface on the cast product.

These and other objects of this invention will become more apparent uponconsideration of the following description.

In general this invention provides an alloy with a low fusing point andgood flow properties which can be cast to a final product having asmoother surface than previous alloys. In particular, the alloy of thisinvention is useful for the manufacture of dentures.

Dentures are made by casting in refractories by the lost wax method. Forvarious reasons it is advantageous to employ a gypsum refractory for thecasting. A gypsum refractory requires the casting to be accomplishedwith a metal which has a fusing temperature of not more than 2500 F. Tocast a metal it is also necessary that the metal have good flowproperties as well as a minimum of impurities.

The alloy of this invention employs four principal ingredients which arechromium, cobalt, nickel and copper. Another ingredient which may beused in the alloy of this invention is beryllium. These ingredientsendow the alloy of this invention with novel and desirablecharacteristics and provide an alloy which is particularly useful in themanufacture of dentures or jewelry.

The following examples serve to illustrate the alloys of the presentinvention but are not intended to limit the same:

2,761,778 Patented Sept. 4, 1956 Example 2 Metal: Per cent by weightChromium 12 to 18 Cobalt 5 to 20 Nickel 45 to 60 Copper 18 to 26Beryllium .25 to 1.0

Example 3 Metal: Per cent by weight Chromium 15 Cobal 5 Nickel 54Copper--- 25 Beryllium 1 These alloys have a melting point between 2300and 2500 F. They can be cast in a gypsum refractory to produce asatisfactory denture.

Among the advantages of this alloy in the manufacture of dentures is thelight color of the alloy. Another advantage is the smooth surface of theproduct cast with this alloy which minimizes the amount and expense offinishing by polishing. As the alloy of this invention is resistant toacid including nitric acid, a denture formed of this alloy resists mouthacids. As this alloy has a low atomic weight the cubic volume occupiedby this alloy is greater per unit of weight and the denture iscorrespondingly less expensive.

The beryllium which may be used in the alloy of this invention serves asa de-oxidizer to remove impurities and may be considered a scavenger inits function in the alloy of this invention.

The copper employed in the alloy of this invention acts to lower thefusing point and gives better flow properties to the alloy in castingand produces a product with a smoother surface.

Various changes may be made in the above described embodiments of thisinvention without departing from the spirit of the invention which islimited only by the appended claims.

I claim:

1. An alloy having as its principal ingredients chromium, nickel, cobaltand copper and containing chromium from 12 to 18 per cent by weight,cobalt from 5 to 20 per cent by weight, nickel from 45 to 60 per cent byweight,

copper from 18 to 26 per cent by Weight and beryllium from .25 to 1.0per cent by weight.

2. An alloy consisting of chromium, nickel, cobalt and copper, thechromium content being 12% to 18% by weight, the nickel content being45% to 60% by Weight, the cobalt content being 5% to 20% by weight andthe copper content being 18% to 26% by weight, said alloy beingcharacterized by a low fusing point and resistance to acids.

3. An alloy consisting of chromium, nickel, cobalt, copper and berylliumand containing, by weight, 12% to 18% chromium, 5% to 20% cobalt, 45% to60% nickel, 18% to 26% copper and .25% to 1.0% beryllium.

4. A denture formed from an alloy consisting of by weight, 15% chromium,5% cobalt, 54% nickel, 25% copper and 1% beryllium.

References Cited in the file of this patent UNITED STATES PATENTS2,521,273 Wissler Sept. 5, 1950 2,636,818 Low Apr. 28, 1953 FOREIGNPATENTS 485,226 Great Britain May 17, 1938

1. AN ALLOY HAVING AS ITS PRINCIPAL INGREDIENTS CHROMIUM, NICKEL,COLBALT AND COPPER AND CONTAINING CHROMIUM FROM 12 TO 18 PER CENT BYWEIGHT, COBALT FROM 5 TO 20 PER CENT BY WEIGHT, NICKEL FROM 45 TO 60 PERCENT BY WEIGHT, COPPER FROM 18 TO 26 PER CENT BY WEIGHT AND BERYLLIUMFROM .25 TO 1.0 PER CENT BY WEIGHT.